The site must be a non-profit organization.

Accessibility: Is the historic site accessible to all visitors within its means (historic, financial, etc.)?

Visitor Readiness: Does the historic site make efforts to post its open hours onsite and are the historic gardens/landscape interpreted in an inclusive and meaningful way?

Maintenance: Is the historic garden maintained? Is it clear the site devotes enough resources to maintaining basic garden standards within its historic design plan?

The site must have a garden and at least one historic house which must be accessible to the public.

The garden(s) must be historically significant. Garden(s) may have been designed by a known designer or reflect an historical garden style or design philosophy. The site should demonstrate an effort to use historic plant varieties where feasible.

The garden and home must be open to the public, exhibit visitor readiness and make an effort to interpret the landscape as part of the overall interpretive scheme for the site.

The site must pay annual dues of $250 for organizations with annual operating budgets under $500,000 and $500 for those with annual operating budgets over $500,000.

The site must participate in CHG-sponsored programs, including the CT Flower and Garden Show, CT's Historic Gardens Day and other events. This involves providing volunteers to staff events.

The site must participate in meetings (approximately 4-6 per year).

The site must agree to promote CHG events in publications and on their websites and social media. Also, the site representative must contribute to the CHG blog and other social media.

The site must have a contact person who can speak for the site on matters of public relations, programming, and budgeting.

Membership will be evaluated on an annual basis.